272 PROTECTION AGAINST INSECTS. 



The larvae hatch in June, and pupate in July in a chamber 

 made in the sapwood. 



The beetles emerge in July and August, and generally pair 

 in the following year. Those, however, which appear early, 

 usually produce another brood within the year, as in the case 

 of the preceding species. 



Generation single or double. The beetle is found in com- 

 pany with the former species, but is rarer, or at any rate more 



Fig. 131. Burrows of M. minor, Hart., on pine sapwood. (Natural size.} 



localised. In the British Isles it has only been found, and 

 that very rarely, in the Dee district of Scotland, but it is so 

 like the much commoner M. piniperda, L., that it is probably 

 overlooked. 



c. Relations to Ihe Forest. 



M. minor, Hart., chiefly attacks the Scots pine, but has 

 also been found on the spruce. It prefers poles, but may 

 attack 50- to 70-year-old trees. The mother-galleries are 

 large, regular, double-armed, and horizontal, with a rather 

 long entrance-burrow, and groove the sapwood deeply (Fig. 131). 



